In this image acquired by NASA’s Terra satellite, melt ponds are visible on August 2, 2013 atop the ice sheet along Greenland’s western coast. (Image: NASA. Post-processing: Tom Yulsman)

The melting season in Greenland peaked in late July, according to the latest report from the National Snow and Ice Data Center. When it is all over, NSIDC scientists project that the season will be much closer to the long-term average than last year — when more of the island’s ice sheet melted than during any other year in the satellite record.

The image above, acquired by NASA’s Terra satellite, shows the surface of the ice sheet in western Greenland pockmarked by blue melt ponds, as well as what appear to be a lacy network of meltwater channels. The ponds are not unusual, as this part of the coast typically does experience melting in the summer.

A good deal of the ice here also seems to show a grayish discoloration. Melting reduces the albedo, or reflectivity, of snow and ice, so the darker tone may be the result of that. But I’m wondering whether dust blowing in from far afield was a contributor. By darkening snow and ice, it can contribute to melting. I’m tracking this down and will post an update when I get an answer.

In the meantime, some details from the NSIDC update:

The period between July 21 and August 19 [click here for a graphic] included the greatest percentage of surface melt extent days for Greenland during 2013, peaking at 44% on July 26 [click here]. However, the overall melt extent for 2012 was far greater, exceeding 40% for several weeks [click on thumbnail at right].

Although melting was much less extensive this year than last, the town of Maniitsoq did experience what may have been the highest air temperature recorded in Greenland since 1958: 78.6 degrees F on July 30.

According to the NSIDC report, strong winds from the south brought unusually warm temperatures to the region. That was compounded by air rushing down from higher elevations. This compresses and thereby warms the air.

The image at the top of this post shows an area not far from Maniitsoq just a day or so after that high temperature was recorded.

Despite that unusual event, “the majority of the ice sheet showed mild to moderately lower-than-average melt duration for this season,” according to the NSIDC report.

There were many more cars on the road this year, more worldwide air traffic, more trucks on the road and more people on the planet. So is global warming man made or not. Do we still call it global warming or are we sticking with climate change?

disqus_atlq8Zmtsd

Don’t be intentionally obtuse. I am a skeptic, but we all know that any anthropogenic effects on climate will manifest in the average over many years, not year to year.

This year’s below average melt is no more proof against global warming than last year’s record was proof for global warming.

I almost hate to see these articles because they aren’t comprehensive and get cherry picked as convenient.

Tom Yulsman

Thank you for these good points. I appreciate it.

Concerning the fact that this piece is not comprehensive: As much as I’d like to, I can’t possibly write a feature article every day. So I report news as I come by it, and over time do the reporting for longer, more comprehensive pieces. I might add that even when I’ve done nuanced, comprehensive stories, they’ve been cherry picked. Usually people believe what they want to believe. As humans, we appear wired to see things through a biasing scrim.

disqus_atlq8Zmtsd

oh, of course. I didn’t mean it in any way as a criticism of your writing or the style in which it was presented.

I understand you can’t and shouldn’t write a 20 page article every two weeks when there is a bit of relevant climate data news.

I just think its a shame that people take an informative article and try to use it as a conclusive article. I’m sure that someone will link this post in a void to “prove” that global melting isn’t on the rise. The irony is that its not only an inaccurate use of the article, but it also undermines the position they are trying to support by making it look farcical.

I truly miss the days when we could discuss issues without them devolving into extremist ideology.

Kudos for making sure to mention both the low melt this year and last year’s record in one go.

On a related note, one thing I would be very interested to see is a chart of estimated melt extent (i assume they have ways to estimate based on soil samples) in Greenland since the end of the pleistocene… preferably with local maxima emphasized.

Tom Yulsman

Many thanks for your constructive comments. I appreciate it. And your question about the melt extent going back to the end of the Pleistocene is a good one. I know just who to ask. So I’ll see what I can find. (After Labor Day! I hope you have a great one.)

disqus_atlq8Zmtsd

I’m excited to see what you turn up.

Tom Yulsman

Don’t hesitate to bug me about this if I don’t come back with an answer in a couple of days. (The blog is not really my ‘day job.’) My email is tom.yulsman@colorado.edu

Tom Yulsman

Here’s the email I just sent to Jim White, a colleague at the University of Colorado and a paleoclimatologist who directs the Institute of Arctic and Alpine Research here:

“Hi Jim,

A thoughtful reader of my ImaGeo blog asked whether we have any decent evidence of the surface melt extent during summers on the Greenland ice sheet since the end of the Pleistocene. We’ve got satellite records since the early 1980s, I think. And NSIDC keeps track of the melt extent anomaly relative to the 1981-2010 average. But do we have data from ice cores and other records extending further back that can help tell us how anomalous surface melt has been recently — or not — in the context of a longer time period?”

Jim is pretty good about responding to questions like this, so I’ll report back what I find out.

Tom Yulsman

I got a quick response from Jim White, my colleague here at the University of Colorado and a paleoclimatologist who directs the Institute of Arctic and Alpine Research. Jim is one of the leading ice core experts, and he has been to Greenland many times. Here’s the question I asked him:

“A thoughtful reader of my ImaGeo blog asked whether we have any decent evidence of the surface melt extent during summers on the Greenland ice sheet since the end of the Pleistocene. We’ve got satellite records since the early 1980s, I think. And NSIDC keeps track of the melt extent anomaly relative to the 1981-2010 average. But do we have data from ice cores and other records extending further back that can help tell us how anomalous surface melt has been recently — or not — in the context of a longer time period?”

And here was his response:

We have a handful of ice cores from north to south in Greenland, all of which record melt layers. So theoretically, we could look at melt extent year by year in a coarse geographic sense. However, if the time of the melt is in the distant past (more than a 200 years or so) the dating can be iffy enough that synchronizing melt layers to the year can be tough. And as the spatial coverage is thin, unless its a doozy, its hard to say that melt seen in one core is spatially representative.

If we can get the sequester lifted, maybe we can get back to doing basic research like determining melt extent in Greenland.”

Bottom line: Getting a scientific answer to your question is very difficult!

Keep in mind that surface melt during a relatively brief span of geological history is one question. Another is how the Greenland ice sheet as a whole has behaved over long periods of time as carbon dioxide and temperature have gone up and down in the past. That’s bread and butter for paleoclimatologists like White. And their findings do give us ample cause for concern about our emissions of greenhouse gases.

disqus_atlq8Zmtsd

I suspected anything they had on that would be pretty speculative. I mean, now that you have had one high melt season, you no longer have the primary resource to determine how old that ice was… the ice itself.

I suppose with enough samples you could determine the last time you had more extensive melt. And like his answer implied, its not like the melt pattern is the same every year. Nature is rarely that convenient.

It really is a shame there isn’t a handy way to privatize basic research funding outside of the areas that have potential to be directly monetized. We have so much red on our federal ledger, it seems likely that reliable funding will be hard to come by for some time.

rgray222

In a way your making my point. The sad fact is global warming believers tried to railroad through that man it the leading cause for global warming without allowing debate or discussion. Politicians tried to tax the weather without debate. Can you only imagine and endless supply of money that they could tap into every time we have record floods, record heat, record cold, record anything without even having an honest debate.
We should be looking furiously into new sources of clean renewable energy. We should be attempting to find cleaner ways to process fossil fuels and looki at ways to improve nuclear energy. After all the energy of the entire universe is nuclear so it must be something we should attempt to refine and understand better.
Every thinking man woman and child on the planet should get behind clean renewable energy but in typical fashion politicians tried to tax a cause which deeply divided people. Our political leaders found a way to divide people on an issue that everyone would have gladly gotten behind!

schmoepooh

Climate is not weather.

Tom Yulsman

Global warming = an increase in the average temperature of the Earth resulting from an accumulation of energy in the atmosphere caused by a buildup of heat trapping gases. Of course, an increase in the global average temperature affects no one directly. So…

Climate change = the changes that occur as a result of global warming — the kinds of things we DO experience more or less directly. For example, increased frequency and intensity of heat waves and droughts.

These terms do not have to be political. They have specific scientific meaning.

Lisa_Belise

Let me use the sentence that 125 International scientists used in a letter to Ban Ki-Moon of the UN last November-

“Global warming that has not occurred cannot have caused the extreme weather of the past few years.”

There has been no statistically significant rise in temperatures GLOBALLY for 16 years. Regional events cannot be blamed on an increase/decrease in the “average temperature of the Earth” even if there had been a significant change. There has ALSO not been any increase in frequency or intensity of heat waves or droughts GLOBALLY. (Where they occur changes due to natural variability in ocean currents, solar radiation, earth’s rotation, etc but there are not more of them nor are they stronger than usual)

Climate changes. All the time. Always has. Always will.

Scientists give meaning to words based on their own biased political agendas to.

schmoepooh

Your question indicates your knowledge is confined to denial sources. The terms are not mutually exclusive. Tom has explained the meanings. References to “climate change” go back to the earliest published reports. 1956 I think.

rgray222

This topic should never have been one that divides people. A clean environment is something that everyone can get behind but liberal politicians saw an opportunity to raise funds through cap and trade tax which politicized the issue. On top of that they attempted to say here is the evidence, accept it as fact , never allowing serious debate or even discussion. Taxing people on changes in the weather is tantamount to taxing people for eating food or putting on your shoes (oh sorry we already pay tax for that). Also the liberal idea/scam for carbon credits was simply paying for a clean conscious. The church did this a thousand years ago and it did not work back then. Global warming/climate change/cap and trade have done incalculable damage to the environment by making the issue political. It will take generations to recover from this arrogant attitude. Everyone suffers when this happens.

schmoepooh

Global warming climate change is one thing. How you deal with it and dodgy politiciansis a seperate issue.

disqus_atlq8Zmtsd

He makes a valid point that the discussion has been so politicized as to make it impossible to trust that you have found a reasonably unbiased source.

You almost have to assume it is biased and see if you can still wrangle conclusions out of what you take for granted as flawed methodology.

schmoepooh

Go with peer reviewed evidence and sound science.

disqus_atlq8Zmtsd

That’s the thing though. Scientists have biases too. The politics of it become relevant to the science because of where funding is coming from and what ideology (yes, scientists are prone to political ideology like the rest of us) the community at large has adopted.

You can probably assume that a group of climatologists working for british petroleum isn’t the best source of climate information. But is a study funded by the Sierra Club any more reliable?

How about government funded studies when the funding is being allocated by politicians that subscribe to extreme ideology?

You aren’t sure if the study is biased, so you rely on peer reviews to tell you. How can you be sure the review isn’t biased?

It can be difficult to suss through and it is truthfully easier to rely on less controversial issues. Air pollution has very well defined effects on human health. Acid deposition is destroying statues and buildings, nevermind what it does to delicate aquatic ecosystems and cloud forests.

Truthfully the measures we take to solve one issue are largely the same measures we take to solve the other.

The economic factors is why the degree of urgency is so important and why the alarmist/denial debate is so heavily politicized.

schmoepooh

Science us like the market. Provided there are no monopolies, anyone can prove otherwise.

disqus_atlq8Zmtsd

I was just reading about Milankovitch theory. Its pretty fascinating.

Just from a historical context, there have been so many regional climate shifts since the start of the Neolithic period that had a massive impact on how agriculture and civilization developed. Small shifts in precipitation can mean everything.

It really is something to contemplate… with our global community and technological resources, are we better equipped to deal with any potential shift in climate (natural or otherwise) or are we too far into the outer range of sustainability to have the flexibility to adapt?

I mean, we’ve not even learned to manage the aquifers we do have. Just food for thought. I’m not sure I even really have a point beyond how interesting the subject is even outside of the political and scientific debate.

Tom Yulsman

Thank you for this excellent perspective!

schmoepooh

I have read ancient people had worked out the smallest Malinkovich cycle. 26000 years is it? They spotted it by plotting shifts in winter equinox at sunrise in places like Stonehenge where light through an aperture can be marked on a heel stone. Eventually a curve is noticed and extrapolation does the rest. Or so the story goes. Theoretically possible I gather.
The climate science calculations take those into account.
The other thing the evidence draws from multiple disciplines, basic high school science, glacier melting, thousands of temperature gushes around the planet, direct records going back 100 years, sea level rise

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ImaGeo

ImaGeo is a visual blog focusing on the intersection of imagery, imagination and Earth. It focuses on spectacular visuals related to the science of our planet, with an emphasis (although not an exclusive one) on the unfolding Anthropocene Epoch.

About Tom Yulsman

Tom Yulsman is Director of the Center for Environmental Journalism and a Professor of Journalism at the University of Colorado, Boulder. He also continues to work as a science and environmental journalist with more than 30 years of experience producing content for major publications. His work has appeared in the New York Times, Washington Post, Audubon, Climate Central, Columbia Journalism Review, Discover, Nieman Reports, and many other publications. He has held a variety of editorial positions over the years, including a stint as editor-in-chief of Earth magazine. Yulsman has written one book: Origins: the Quest for Our Cosmic Roots, published by the Institute of Physics in 2003.